1. Field of the Invention
This invention relates to a service vehicle typically equipped with a hydraulically driven work implement such as a hydraulic excavator or another construction machine.
2. Description of the Related Art
Relatively small hydraulic excavators having a turning diameter smaller than the width of the vehicle main body are known. In the case of hydraulic excavators, the upper swing body is mounted on the vehicle main body, which has a pair of lower running bodies (generally crawlers). In the case of such a small hydraulic excavator, the upper swing body turns within the width of the vehicle main body, including the width of the paired lower running bodies, so that it does not move out of the width of the vehicle. Therefore, such a hydraulic excavator is advantageously used in city centers, residential areas and other areas where the lot is normally small, because it can make a small turn.
Canopy type models and cab type models of hydraulic excavators are available so that either model can be selected at the time of purchase. The canopy type model is equipped only with a canopy arranged above the operator seat so that it is less costly and the operator can get onto and away from the seat without difficulty. On the other hand, the operator seat of the cab type model is enclosed by a box-like cab so that the operator is reliably protected against rainfall and wind and therefore can comfortably work in the cab.
Meanwhile, dedicated parts are developed and prepared conventionally for small and large hydraulic excavators based on the size of the vehicle. Such a process of developing parts is rather costly. In view of the current circumstances where cost reduction is an imposing requirement to be met regardless of the size of the machines, efforts are being made to develop parts that can be commonly used for machines of any size for the purpose of cost reduction.
Additionally, to enable the hydraulic excavator to be operated comfortably, it is necessary that sufficient space be provided around the operator seat. Therefore, there is a practice of mounting a cab developed for a large hydraulic excavator on a small one in an effort to provide parts that are commonly used for all the types. However, when a cab developed for a large hydraulic excavator is mounted on the upper swing body of a small hydraulic excavator, the cab disadvantageously extends past the upper swing body to a large extent.